This invention relates to the problems encountered in passage of communication, power and other cables, wires and conduits therefor through openings in cement or other material structural members for connection of said cables or conduits, from cable raceways or other sources, to lighting, communication, electronic and other fixtures and devices. Such cables are conventionally formed with center cores of wire, tape, or other center material, enclosed in insulation. Insulation, adequate at room temperature, burns off and exposes center cores of cables and wires at the greatly elevated temperatures that occur in the case of fires. Thus spaces and openings are formed for ready passage of excess heat, smoke and flames, on occurrence of fires or highly elevated temperatures. In practice, therefor, devices through which cables pass heretofore provided ready and effective passageways or chimneys for smoke, flames and excess heat, with resultant great loss of life and property. In addition to such serious consequences through cable passage devices on burning off the insulation of cables and wires, heat, smoke and flames, once started, move and flow with increasing rapidity, accelerating, in a domino effect, from floor to floor, and defying efforts to contain or stop it, multiplying the risk of injury and loss of life to persons in the building as well as to fire fighting personnel.
Such dangerous fire conditions are further aggravated when plastic cable conduit, which, in many installations, is more convenient and time saving than metal, and less costly, is used. Such plastic cable conduit, efficient at room temperatures, readily burns at highly elevated temperatures. Steel cable conduit readily conducts heat and thus also serves to aid the progress of fire and excess temperatures.
The device of this invention overcomes the foregoing and other deficiencies in prior art devices by providing automatic, efficient and effective means for sealing cables in a wall, floor or other structure on occurrence of fire or highly elevated temperatures, thus assuring safety in use and operation and enhancing the fire and safety ratings of the structures wherein the invention is utilized.